Drinking the Sea

摘要

IN THE FOURTH CENTURY B.C.E., ARISTOTLE DESCRIBED one way to make seawater potable: "Salt water when it turns into vapor becomes sweet, and the vapor does not form salt water again when it condenses." Aristotle was describing the process of distilling seawater. The setup is straightforward. A solution-in this case, salt water-containing components of different boiling points is heated in a container with one opening. Attached to this exit is a cooled condenser that turns vapor back into liquid. It is oriented so that the condensed liquid-the distillate-can be collected in a second container.